论文部分内容阅读
利用荧光定量PCR和高通量测序的研究方法,比较了3种种植模式(燕麦单作,O;大豆/燕麦,OSO;绿豆/燕麦,OMO)对燕麦土壤固氮微生物数量和群落组成的影响.结果表明:与大豆和绿豆间作显著改变了燕麦土壤的理化性质.燕麦土壤固氮微生物nif H基因拷贝数为每克干土1.75×10~(10)~7.37×10~(10),拔节期和成熟期OSO和OMO中nif H基因拷贝数分别是O中的2.18、2.64和1.92、2.57倍,且各处理成熟期nif H基因拷贝数显著低于拔节期.样品稀释性曲线和覆盖度结果表明,各样品nif H基因测序结果可靠.与绿豆间作显著提高了燕麦土壤nif H基因的多样性.各样品固氮微生物属水平上优势类群均为Azohydromonas、固氮菌属、慢生根瘤菌属、Skermanella和在属水平上无法归类的固氮微生物,但各优势类群相对丰度存在差异.样品OTU的venn分布和主成分分析显示,拔节期和成熟期nif H基因群落结构存在差异,两个生育时期OSO和OMO具有更相似的nif H基因群落结构.表明与大豆和绿豆间作可显著提高燕麦土壤固氮微生物的数量,并影响固氮微生物的群落组成.
The effects of three planting patterns (oat single crop, O; soybean / oats, OSO; mung bean / oats, OMO) on nitrogen fixation of microbial population and community composition in oats were compared using fluorescence quantitative PCR and high throughput sequencing. The results showed that the intercropping with soybean and mung bean significantly changed the physicochemical properties of oat soil.The nif H gene copy number of oat soil fixing microorganism was 1.75 × 10 ~ (10) ~ 7.37 × 10 ~ (10) per gram of dry soil, The nif H gene copy number in mature OSO and OMO was 2.18, 2.64 and 1.92, 2.57 times respectively in O, and the copy number of nif H gene in each mature stage was significantly lower than that in the jointing stage.The results of dilution curve and coverage showed , And the results of nif H gene sequencing of each sample were reliable.The intercropping with mung bean significantly enhanced the nif H gene diversity in oat soil.The dominant groups of nitrogen-fixing microorganisms in each sample were Azohydromonas, Azotobacter, Bradyrhizobium, Skermanella and However, the relative abundance of each dominant group is different.The venn distribution and principal component analysis of OTU showed that the structure of nif H gene at jointing stage and mature stage differed, and the two fertility OSO and OMO had similar nif H gene community structure during the period, indicating that intercropping with soybean and mung bean could significantly increase the number of nitrogen-fixing microorganisms in oat soil and affect the community composition of nitrogen-fixing microorganisms.